swiftui .fileimporter无法在真实设备上工作

Question

步骤复制：

使用SwiftUi创建一个新的Xcode项目。

按照代码：

DocumentPickerViewController

documentPicker.swift：

import SwiftUI

struct ContentView: View {
    @State var sShowing = false
    @State var uShowing = false
    
    @State var showAlert = false
    @State var alertText = ""
    var body: some View {
        VStack {
            VStack {
                Button("Test SWIFTUI") {
                    sShowing = true
                }
            }
            .fileImporter(isPresented: $sShowing, allowedContentTypes: [.item]) {result in
                alertText = String(describing: result)
                showAlert = true
            }
            VStack {
                Button("Test UIKIT") {
                    uShowing = true
                }
            }
            .sheet(isPresented: $uShowing) {
                DocumentPicker(contentTypes: [.item]) {url in
                    alertText = String(describing: url)
                    showAlert = true
                }
            }
            .padding(.top, 50)
        }
        .padding()
        .alert(isPresented: $showAlert) {
            Alert(title: Text("Result"), message: Text(alertText))
        }
    }
}

在MAC催化剂上运行该项目以确认其正常工作。

在真实的iPhone上浏览它。 there是一个视频，显示了问题：

https：//vimeo.com/1059300326/22cc4a1861？share =copy

我无法在运行iOS 18.1.1的真实iPhone上重现这一点，但是这里可能发生的事情是SwiftUi

4. import SwiftUI
   import UniformTypeIdentifiers
   
   struct DocumentPicker: UIViewControllerRepresentable {
       let contentTypes: [UTType]
       let onPicked: (URL) -> Void
   
       func makeCoordinator() -> Coordinator {
           Coordinator(self)
       }
   
       func makeUIViewController(context: Context) -> UIDocumentPickerViewController {
           let documentPicker = UIDocumentPickerViewController(forOpeningContentTypes: contentTypes, asCopy: true)
           documentPicker.delegate = context.coordinator
           documentPicker.modalPresentationStyle = .formSheet
           return documentPicker
       }
   
       func updateUIViewController(_ uiViewController: UIDocumentPickerViewController, context: Context) {}
   
       class Coordinator: NSObject, UIDocumentPickerDelegate {
           var parent: DocumentPicker
   
           init(_ parent: DocumentPicker) {
               self.parent = parent
           }
   
           func documentPicker(_ controller: UIDocumentPickerViewController, didPickDocumentsAt urls: [URL]) {
               print("Success!", urls)
               guard let url = urls.first else { return }
               parent.onPicked(url)
           }
   
           func documentPickerWasCancelled(_ controller: UIDocumentPickerViewController) {
               print("Picker was cancelled")
           }
       }
   }

   认为

   sheet

   没有试图自行自我，因为它正在使用Uikit Apis。 如果您出于某种原因需要使用UIDocumentPickerController

   （也许您仍然支持iOS 13？），我建议将演示代码移至Uikit的一边，而不是使用SwiftUi
UIDocumentPickerController

。换句话说，

Answer 1

应该返回一个虚拟视图控制器，其唯一的作业是呈现文档选择器。

makeUIViewController

您可以将其添加为某种视图的

struct DocumentPicker: UIViewControllerRepresentable {
    let contentTypes: [UTType]
    @Binding var isPresented: Bool
    let onPicked: ((URL) -> Void)?
    
    func makeUIViewController(context: Context) -> UIViewController {
        context.coordinator.vc
    }
    
    func updateUIViewController(_ uiViewController: UIViewController, context: Context) {
        context.coordinator.contentTypes = contentTypes
        context.coordinator.onPicked = {
            isPresented = false
            onPicked?($0)
        }
        if isPresented {
            context.coordinator.present()
        }
    }
    
    @MainActor
    class Coordinator : NSObject, UIDocumentPickerDelegate {
        let vc = UIViewController()
        var contentTypes: [UTType] = []
        
        var onPicked: ((URL) -> Void)?
        
        func present() {
            let documentPicker = UIDocumentPickerViewController(forOpeningContentTypes: contentTypes, asCopy: true)
            documentPicker.delegate = self
            documentPicker.modalPresentationStyle = .formSheet
            vc.present(documentPicker, animated: true, completion: nil)
        }
        
        func documentPicker(_ controller: UIDocumentPickerViewController, didPickDocumentsAt urls: [URL]) {
            print("Success!", urls)
            guard let url = urls.first else { return }
            onPicked?(url)
        }

        func documentPickerWasCancelled(_ controller: UIDocumentPickerViewController) {
            print("Picker was cancelled")
        }
    }
    
    func makeCoordinator() -> Coordinator {
        Coordinator()
    }
}

：

background